Re: 25-06 rem ackley improved
Ackley Improved round is different in several ways, but uses 25-06 rem case to begin with... loaded 25-06 rem rounds are fired in the AI chamber and the cases are fire formed i.e. "improved" to the AI chamber... shoulder is "blown" forward, creating a different shoulder angle and creating more powder space in the newly formed 25-06 AI round... shortening the neck some, in the process... usually takes pretty stout 2-3 rounds to fully form the new AI case...
basic procedure would be similar in "ackly improving" other rounds as well, such as .243AI; .260AI etc
pretty popular "improvement" in several calibers